--  The latest poll shows the marriage amendment defeated by a razor-thin margin in Minnesota, but results are well within the margin of error.  The SurveyUSA/KSTP poll finds 48 percent against amendment and 47 percent in support, the first time in that survey that "no" votes have a higher percentage.  A Public Policy polling survey released Saturday also shows the marriage amendment defeated, although by a somewhat larger margin.  Advocates on both sides of the  issue are using the last hours before Tuesday's election to get out the vote.